关键词: SARS, 疫苗, 重组多表位肽, 表位疫苗

Abstract: Objective To obtain recombinant poly-epitope peptides based on selected linear B cell epitope and evaluate its probability as epitope vaccines. Methods Poly-epitope peptides were expressed by prokaryotic expression vector with multi-epitope peptides coding gene fragments, which were obtained through gene engineering technology. The cross-reactivity of tested peptides with the SARS patients sera and titers to serum from rabbits immunized with recombinant poly-epitope peptides were determined by ELISA. Their specificity was measured by Western blotting, while SARS-CoV-neutralizing response was identified by neutralization technology. Results PEP1 and PEP2 encoding gene fragments were successfully obtained and the recombinant poly-epitope peptides rPEP1 and rPEP2 were successfully expressed. Cross-reaction rate of purified rPEP1 and rPEP2 with the patient serum were 88.7% and 97.2%, respectively. They can be recognized by immunized rabbits serum, binding titers were 1×106 and 5×105, and SARS-CoV neutralizing efficiency were 70% and 80% respectively. Conclusions Recombinant poly-epitope peptides rPEP1 and rPEP2 with high cross-reactivity, strong immunogenicity were successfully obtained. It provided experimental basis for the preparation of poly-epitope peptide vaccine.